Boston’s Handel and Haydn Society has expanded its free digital programming, with content including a nine-week “Summer of Beethoven” festival, a podcast hosted by Principal Cello Guy Fishman, and two new 24-hour internet radio stations, one featuring H+H instrumental recordings, the second mixing in other music. “Summer of Beethoven” launched on July 4 and includes live and recorded performances of the composer’s symphonies, concertos, choral works, and chamber music; a feature on H+H’s effort to commission new music from Beethoven in the 1820s; and, in August, a weeklong Beethoven takeover of online station Radio H+H. The Handel and Haydn Society podcast “Tuning In” includes an interview with Concertmaster Aisslinn Nosky discussing Vivaldi’s The Four Seasons and insights from H+H musicians and staff about the music they love. Other digital offerings from the Handel and Haydn Society include “Musicians From Home,” a collection of personal performances from H+H musicians filmed at their homes; “Musical Pairings,” during which H+H musicians discuss the connections, bonds, and creation of musical beauty through their instruments; and the “H+H Listening Room,” recordings of past H+H performances and clips about various musical offerings.